Synonyms of interminable

1 Syllable

long, dull

2 Syllables

undying, unbound, longish, lengthier, nonstop, full-out, lengthy, termless, boundless, constant, boring, endless, looped

3 Syllables

ceaseless, persistent, perpetual, unended, bulldogged, eternal, round-the-clock, aeonian, unwaning, day-and-night, timeless, continual, long-winded, long-drawn-out, immortal, immense, protracted, limitless, permanent, incessant, continuous, unending, unceasing

4 Syllables

unlimited, wearisome, unremitting, around-the-clock, oft-repeated, sempiternal, never-ending, measureless, all-embracing, everlasting, infinite, never-ceasing, phoenixlike

5 Syllables

self-perpetuating, interminate, immeasurable, illimitable, supertemporal, uninterrupted